Properties

Label 2.256.acd_bwf
Base field $\F_{2^{8}}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{2^{8}}$
Dimension:  $2$
L-polynomial:  $1 - 55 x + 1253 x^{2} - 14080 x^{3} + 65536 x^{4}$
Frobenius angles:  $\pm0.0614721139001$, $\pm0.236081656579$
Angle rank:  $2$ (numerical)
Number field:  4.0.2623305.2
Galois group:  $D_{4}$

This isogeny class is simple and geometrically simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $52655$ $4261105875$ $281443602695120$ $18446895257327125875$ $1208926453070853840633875$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $202$ $65018$ $16775347$ $4295002498$ $1099512203902$ $281474971974263$ $72057593673724042$ $18446744065417946338$ $4722366482765509048267$ $1208925819614473480497698$

Jacobians and polarizations

This isogeny class contains a Jacobian, and hence is principally polarizable.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2^{8}}$.

Endomorphism algebra over $\F_{2^{8}}$
The endomorphism algebra of this simple isogeny class is 4.0.2623305.2.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.256.cd_bwf$2$(not in LMFDB)